Changes

I followed the same data design as in [[VCDB20H1]]. Essentially the specification pulls everything, even things that aren't needed like incomplete M&As or withdrawn IPOs, or funds or investments that aren't venture capital, all the way to the present (the pull was done on 11/17/2020), and then place restrictions on the data later. Crucially, the pulls no longer use the venture-related flag, so the data contains private equity and other deals, and the data does contain as well as secondaries and purchases. Note that the M&As are pulled separately for public and private acquirers, and in chunks by year to keep the request sizes manageable.